The U.S. is more cautious, with an official saying the five Muslims from suburban Virginia apparently weren't on the verge of violence. They may be handed over to the FBI.

Another member of the group, Umar Farooq Chaudhry, 24, born in Pakistan and naturalized three years ago, apparently provided a place for them to stay.

Pakistani police said the house where the group was captured in Sargodha belongs to Fahim Farooq, who is Farooq Chaudhry's uncle. But U.S. officials said they believe the house belongs to Farooq Chaudhry's father. The father is in Pakistan and has been trying to help the jailed men, the U.S. anti-terrorism official said.

The other men were all born in the United States, U.S. officials said. Pakistani American Waqar Khan, 22, is the only one with a criminal record, the anti-terrorism official said. In 2006, he was convicted of misdemeanor embezzlement and received a 12-month suspended sentence, the official said.

Amin Yemer, 18, is of Ethiopian descent and lived for a time in Seattle, according to U.S. and Pakistani officials. Ahmad Minni, 20, is apparently the son of Ethiopian immigrants, a Pakistani official said.

The group lived in modest houses, townhomes and apartments within a few blocks of one another. They were apparently roommates at different points, officials said.

Hooper, of CAIR, said the council was exploring the Internet as a prime source of extremist viewpoints that may have helped radicalize the men.

"That's why," he said, "we're putting together, over the next few weeks, a nationwide campaign challenging religious extremism and offering a mainstream viewpoint."